Carburetor by-pass

ABSTRACT

An air by-pass device for internal combustion engines comprising a first valve assembly positioned between the carburetor and the intake manifold and having a passageway providing fluid communication between the carburetor and manifold, and a valve member in the passageway for closing off the passageway to the fuel mixture, means for conveying ambient air to the intake manifold through the first valve assembly, a second valve assembly operatively connected with the air conveying means for controlling the flow of air therein, first and second solenoids for operating respectively the first and second valve assemblies simultaneously, and an electric line connecting the solenoids with a source of electric current and including switches responsive to the accelerator pedal position and the flow of air from the engine cooling fan so that when the accelerator pedal is released at a time when the air flow from the engine cooling fan exceeds the normal flow at idle, the solenoids will be energized for cutting off the fuel flow to the engine and admitting ambient air thereto.

Normal carburetion injection systems feed fuel into the engine even whenthe pressure is taken off the gas pedal because of the vacuum producedin the cylinders on the downstroke of the piston and this invention willovercome this problem by by-passing air into the cylinders and closingoff the fuel supply, and will only allow fuel flow to keep the motorrunning at idling speeds or when pressure is again applied to the gaspedal.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of the apparatus forming this invention;

FIG. 2 is a top plan view of the device of FIG. 1;

FIG. 3 is a transverse section view of the device of FIG. 1;

FIG. 4 is an enlarged view of a portion of the device shown in FIG. 3;and

FIG. 5 is a schematic drawing of the electrical control system.

As illustrated on the drawings, the invention primarily consists of anair intake, air passage chamber, valve and solenoid arrangements.

The solenoids are operated electrically through manual switch 13 on thedashboard, switch 14 operated by the gas pedal arm and a sail switch 15operated by air flow from the radiator fan.

The manual switch is normally left in the "on" position as it isprimarily a safety cut off and ensures that power will be available forthe electrical control system.

At normal or high engine speeds and with the gas pedal depressed, switch14 is open and air flow from the radiator fan keeps the sail switch 15closed and the engine operates normally drawing fuel through thecarburetor.

When pressure is taken off the gas pedal, switch 14 is closed thuscompleting the electrical circuit and solenoids 2 and 4 are energized.Solenoid 4 through linkage 8 closes the butterfly valve 3 thus closingoff fuel flow through the carburetor and at the same time, solenoid 2pulls up plunger and valve 10 from the seat allowing air to pass intothe intake manifold through intake openings 1, around the outside of thesolenoid coil, through openings in casting 17 and opening 12 of flange7.

As the speed of the engine decreases to a predetermined setting, thesail switch contact opens because of reduced air flow and the solenoidsare then de-energized and engine then operates again under normalcarburetion injection. This avoids the problem of the engine stoppingwhile parking, in low speed operation or going downhill.

Rib spacers 18 are provided in the solenoid casing allowing air aroundthe coil.

The air intake is provided with filter media 9 and screen 17 and thecoil is held in place by a spring clip.

The air intake assembly is removeable for cleaning while the completeintake and solenoid assembly is removeable at flange 5 for servicing.

Solenoid 4 is held in place by clamp 6 and is also removeable forservicing or replacement.

FIG. 4 is an enlarged view of the flange assembly 7 showing thebutter-fly valve 3, insert 11 and air passages 20 and illustrates howthis flange assembly fits between the carburetor flange 19 and intakemanifold flange 16.

Solenoids 2 and 4 are protected from current overload by fuses 21.

Minor modifications can be made to the invention by eliminating solenoid2 and operating two butterfly valves from solenoid 4 by a linkagearrangement. The air intake arrangement shown can also be deleted withthe air taken from the air intake normally provided on the engine.However, the principle of operation remains the same furthermore, thisdevice may be modified to fit any carburetor and intake manifoldflanges.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. An air by-pass devicefor internal combustion engines comprising:a first valve assemblyadapted to be sealingly mounted between a carburetor assembly and theengine intake manifold, said valve assembly including a housing having apassageway extending therethrough providing fluid communication betweensaid carburetor and said manifold, and a valve member operable to movebetween open and and substantially closed positions in said passageway,means for conveying ambient air to said intake manifold through saidfirst valve assembly, a second valve assembly operatively connected withsaid air conveying means for controlling the flow of air therein, firstand second solenoids for operating respectively said first and secondvalve assemblies simultaneously, an electric line for connecting saidfirst and second solenoids with a source of electric current, a normallyclosed manual switch in said electric line capable of interrupting theelectric current, a switch member in said electric line andinterconnected with the accelerator such that said switch is open whenthe accelerator pedal is depressed and closed when the accelerator pedalis released to idle position, a sail switch in said electric line andpositioned in the flow of air from the engine cooling fan and adjustedso as to be closed when the air flow from the fan exceeds the normalflow at idle and open when the air flow equals the normal flow at idle,whereby when said accelerator pedal is released at a time when the airflow from the engine cooling fan exceeds normal flow at idle, said firstand second solenoids will be energized for closing said first valveassembly and cutting off fuel flow to the engine and opening said secondvalve assembly for admitting ambient air to the engine.
 2. An airby-pass device as in claim 1 and wherein said first valve assembly andsaid air conveying means are integrally associated, external air beingadmitted to said housing by means of an inlet port in said passagewaybeneath said valve member.
 3. An air by-pass device as in claim 2 andwherein said passageway comprises upper and lower concentricinterconnected bores, said lower bore being substantially larger incross-section that said upper bore, and a sleeve member positionedwithin said upper bore and of length sufficient to extend substantiallythrough said housing, such that the external surface of said sleevemember and the internal surface of said lower bore define an annularchamber into which air may pass via said inlet port.
 4. An air by-passdevice as in claim 3 wherein said valve member is a butterfly valvemounted on shaft means such that the axis of rotation of said valve issubstantially normal to said passageway, and wherein said shaft meansextends outwardly of said housing.
 5. An air by-pass device as in claim4 wherein said first solenoid is connected to said valve shaft means soas to affect rotation thereof when solenoid reponds to an electricalsignal.
 6. An air by-pass device as in claim 5 wherein said airconveying means comprises a passageway formed as an extension of saidhousing and adapted to an end remote from said housing to beinterconnected with said second valve assembly.
 7. An air by-pass deviceas in claim 1 wherein said second valve assembly comprises: a housingopen at its upper and lower extremities, the lower open end beingadapted for fluid interconnection with said air conveying means, achamber within said housing formed at one end into a valve seat; saidsecond solenoid being positioned within said chamber and held in spacedrelation from the sides of such chamber by rib means; and a valve memberactuated by said solenoid to move from a normally closed positionagainst said valve seat to an operable open position away from saidseat.
 8. An air by-pass device as in claim 7 wherein air intake meansare releasably mounted on the upper open end of said housing said meansincluding an air filter and screen.